KABUL — The suicide bomber who struck in Kabul on Tuesday killed four high-ranking NATO officers who had been on a brief visit, military officials confirmed Thursday. They said the victims included two full colonels, an American and a Canadian, and two American lieutenant colonels.

It was the largest number of ranking officers from the U.S.-led forces here killed in any insurgent attack since the Afghan war that ousted the Taliban from power began more than eight years ago.

The attack Tuesday in Kabul came as the officers were driving in a convoy of armored sport-utility vehicles during the morning rush. A suicide bomber in a minibus drove into their convoy, killing the four officers, two other U.S. servicemen and 12 Afghan civilians in a passing bus.

Canadian military officials identified the colonel who was killed Tuesday as Geoff Parker, 42, from Oakville, Ontario, an officer of the Royal Canadian Regiment, and the highest-ranking Canadian to die in the Afghan conflict. He was to become the deputy commander of the Stability Division of NATO’s southern command in Kandahar on Nov. 1, and was on an assessment visit when the attack took place.

Similarly, the U.S. colonel, whom the Pentagon identified Thursday as John McHugh, 46, from New Jersey, was also on an assessment visit as part of his assignment for the U.S. Army Battle Command Training Program.

The two lieutenant colonels, Paul Bartz, 43, of Waterloo, Wis., and Thomas Belkofer, 44, of Perrysburg, Ohio, were both on a familiarization visit in advance of assignments in Afghanistan, according to a spokesman for the American military in Kabul, Lt. Col. Joseph Breasseale.

The other two U.S. soldiers killed Tuesday were the officers’ drivers, and both had been assigned to Kabul since the fall. The Pentagon identified them as Staff Sgt. Richard Tieman, 28, of Waynesboro, Pa., and Specialist Joshua Tomlinson, 24, of Dubberly, La.

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